1. Field of the Invention
The present invention relates to an apparatus for controlling the temperature of materials in a flowable state as they flow through a barrel and for insulating the barrel. In particular, the present invention is directed to modular heating and cooling elements for controlling temperature utilizing removable and replaceable heating or cooling elements.
2. Prior Art
It is known in the plastics and polymer industries to utilize injection and/or extrusion equipment to form or manufacture components and products. Plastic or polymer resins along with additives are subjected to hot temperatures in order to convert the plastic or polymer resins into a flowable material. The material is injected or forced under pressure through a barrel before directing into a mold cavity or die. The barrel may include a rotating screw which mixes the materials and moves them through the barrel. Thereafter, the molten plastic or resin leaves the barrel and enters the mold or die.
In order to insure optimum flow characteristics, the barrels are often equipped with heating or cooling mechanisms in order to control the temperature of the compound. Assignee's prior patent, U.S. Pat. No. 6,486,445, entitled “Vacuum Cast Ceramic Fiber Insulated Band Having Heating and Cooling Elements,” illustrates an example of a ceramic fiber insulated band. The flow characteristics of the fluid material are dependent upon the ability to control the heat applied to the barrel as the fluid passes therethrough.
Notwithstanding the foregoing, it would be desirable to provide an apparatus for controlling the temperature of materials in a flowable state as they flow through a barrel wherein individual temperature controlling mechanisms are removable and replaceable.
In addition, it would be desirable to provide an apparatus for controlling the temperature of materials in a flowable state as the materials flow through a barrel wherein a cover or jacket surrounds the band of the apparatus to protect the band from damage or dirt and to provide a receptacle for a temperature sensing element.